Kids and Hacking: Blind Robotics
If you are a Hackaday reader, it is a good bet that when you were a kid there was some adult who infected you with the madness you have for science, engineering, tinkering, or whatever it is that brings you here. Maybe it was a parent or a teacher. For many of us, it was a local ham radio operator. But it was probably someone who had the passion for this kind of thing and you caught it.
Paying that debt forward can be very rewarding. Schools and youth organizations are always looking for people to share their passions with …read more
Video FPGA with No External A/D
You have an old PC with a nonstandard RGB video out and you need to bring it to a modern PAL TV set. That’s the problem [svofski] had, so he decided to use an Altera-based DE1 board to do the conversion. Normally, you’d expect reading an RGB video signal would take an analog to digital converter, which is not typically present on an FPGA. Instead of adding an external device, [svofski] used a trick to hijack the FPGA’s LVDS receivers and use them as comparators. …read more
See Actual Microwaves — No More Faking It
Last week we saw a lot of interest in faux visualization of wireless signals. It used a tablet as an interface device to show you what the wireless signals around you looked like and was kind of impressive if you squinted your eyes and didn’t think too much about it. But for me it was disappointing because I know it is actually possible to see what radio waves look like. In this post I will show you how to actually do it by modifying a coffee can radar which you can build at home.
The late great Prof. David Staelin …read more
Pulse Density Modulation
[esot.eric] was trying to drive a motor and naturally thought of using pulse width modulation (PWM) to control the motor speed. However, he found that even with a large capacitor, his underpowered power supply would droop before the PWM cycles were complete. So instead of PWM he decided to experiment with pulse density modulation.
The idea is to use smaller pulses over a longer period of time and make the average power equal to the percentage motor speed desired. With a PWM system, for example, if the time period is T, a 50% PWM drive would have the drive high …read more
The Rise of the Rural Hacker
On the far side of the Boso peninsula lies Kamogawa. This isn’t the Japan of LEDs, Otaku and maid cafes, or that of wage slave salarymen collapsing from exhaustion. This is the Japan of rice farmers and fields, fresh fish and wild boar, electron microscopes and gigabit fiber, SMD assembly and 500Mhz 5 Gigasample oscilloscopes.
The world has changed. In the 20th century the life of a rural hacker was a constant hunt for technological innovation. We scratched around for whatever we could find. A (usually national) periodical would give its monthly injection of technological curios. And knowledge was locked …read more